import pandas as pd
import numpy as np

# series 是列
s = pd.Series([1, 3, 5, np.nan, 6, 8])
print(s)

dates = pd.date_range('20130101', periods=7)
print(dates)

'''
np.random.randn(6, 4): 生成一个6行4列的二维数组
index: 指定行索引
columns: 指定列名
'''
df = pd.DataFrame(np.random.randn(7, 5), index=dates, columns=list('ABCDE'))
print(df)
